Explain call by reference, C/C++ Programming

Assignment Help:

Call by Reference

Passing variables(parameters) to a function in C can be done in two ways - pass by value, also called as call by value and pass by address or also known as call by address. C++ though , gives one more way to call a function - call by reference. In call by value , a copy of the actual contents of the variables is passed to the function. In this case, alters made to the formal variable , as they are called, are not reflected back in the calling function. Passing an address permits changes to be made directly to the memory, which are occupied by the actual variable.

Though, a call by address requires the formal variable to be considered as pointer and therefore the indirection operator has to be used with them. A reference on the other hand, is another name, for a previously explained variable. In other words, after a reference is explained for a particular variable, using its original name as well as the reference can refer to the variable. Hence, a reference is nothing but an alias.

 Thus not passing a copy (call by value) saves time and is efficient. It does not have to make a temporary variable /. And not passing the address(call by address), eliminates the use of pointers in the called functions. But, at the same time, the changes made to a formal variable , using its reference or alias can be reflected back in the calling function.

 


Related Discussions:- Explain call by reference

Explain brief about class and objects, Question 1 Write a program that acc...

Question 1 Write a program that accepts a 3x3 matrix from the user and finds the transpose of it Question 2 Explain Brief about class and objects. Also describe friend functi

Program create a user defined data structure - c++ program, Create a user-d...

Create a user-defined data structure (struct) called Node that represents a node within a linked list where the "data" stored in each node is a pointer to a Car object.    a) Wr

Array, how to do an array

how to do an array

#title. c program on pebble merchant, #questThere is a pebble merchant. He ...

#questThere is a pebble merchant. He sells the pebbles, that are used for shining the floor. His main duty is to take the length of the room’s sides. But he sometimes mistakes doin

Minimum shelf, #At a shop of marbles, packs of marbles are prepared. Packet...

#At a shop of marbles, packs of marbles are prepared. Packets are named A, B, C, D, E …….. All packets are kept in a VERTICAL SHELF in random order. Any numbers of packets with the

What are the benefits of using friend classes, What are the benefits of usi...

What are the benefits of using friend classes? - Friend classes are useful when a class wants to hide features from users which are required only by another, tightly coupled cl

Bouncing Ball, Create an applet that bounces a blue ball inside an applet u...

Create an applet that bounces a blue ball inside an applet using Thread. The ball (diameter is 10) will start at position (0,0). When the ball hits the edge of the applet, the ba

Can any constructor throw an exception?, Can any constructor throw an excep...

Can any constructor throw an exception? How to handle error while the constructor fails?

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd